public static String getSixNum() {
String str = "0123456789";
StringBuilder sb = new StringBuilder(4);
for (int i = 0; i < 6; i++) {
char ch = str.charAt(new Random().nextInt(str.length()));
sb.append(ch);
}
return sb.toString();
}
public static String getSixNum() {
String str = "0123456789";
StringBuilder sb = new StringBuilder(4);
for (int i = 0; i < 6; i++) {
char ch = str.charAt(new Random().nextInt(str.length()));
sb.append(ch);
}
return sb.toString();
}